Threaded Inserts - VERY stupid question

[James Jayko]

I never use threaded inserts; used them once in poplar. They worked fine for what I needed, but were definitely not driven in squarely to the wood.

So questions...would you guess that was because it was poplar and poplar is super soft? Bad luck? Or is there a method to drive them in properly / squarely? I've seen some folks install the fastener, then chuck it up in the drill press and turn it by hand. This seems like its way overkill, but is that the best way to drive them squarely?

Yes, I do realize how precious I sound asking such a dumb question lol

[Prashun Patel]

You're not being precious. Threaded inserts are tricky to install and you are right to ask.

Driving them with a drill press is the easiest way to get them square. I prefer the inserts that allow a slotted driver to seat. I can't stand using a double nutted bolt to screw in the inserts. Despite best efforts, it's hard to keep it from seizing and then unscrewing the insert. You could ca glue the insert but with a bolt in there, there's a risk you'll lock the bolt.

Also, they are SUPER EASY to cam out in the hole, so make sure you drive slowly, and keep backing out. If I am successful (like 50% of the time) I wick a drop of CA glue around the outside after fully seated.

If I am not successful and the insert cams out, I epoxy. Now, epoxy is a tricky, because you can't let it squeeze up into the insert. So, I drill the hole a bit deeper, tape the bottom of the insert with a button of tape, and then thread a waxed bolt into the hole. You can use any of several methods to keep the bolt perpendicular to the face of the board.

[Jim Becker]

I agree with Prashun...it's not the wood, but the challenge with installing the inserts properly and straight. It's true that softer wood species benefit from inserts that have deeper threading...just like when choosing screws for the same materials. It's a good practice to lightly chamfer the pilot hole just a little to help with starting things in I've found.

And to keep this real, I found it very challenging to install the four threaded inserts I used to secure the rail assemblies for my slab flattening table not long ago. It wasn't poplar. It was simple 2x material which is worse! I had a devil of a time getting those thangs in straight. In fact, I had to relocate one because the first position just didn't cooperate.

[Kent A Bathurst]

I have never gotten one in square by freehand.

My method - assume 1/4 - 20 for arguments sake:

3" hex-head bolt and 2 nuts.
1-1/2" x 1-1/2" x 6" chunk of wood.

1. drill 1/4" hole through the middle of the wood, using your drill press
2. Put the bolt through the hole
3. Thread both nuts on the end of the bolt, and jam-lock them against each other. Leave 3/8" - 1/2" of bolt exposed.
4. Use 2 scraps of wood of equal thickness as supports under the ends of the chunk of wood with the bolt and nuts.
5. Thread the insert on the end, and put a bit of wax on the insert threads.
6. Straddle the target hole, and use fingers then a wrench to seat the insert.

Back the hex bolt out, and save the chunk for next time, with the nut and bolts still there.

My chunk has 4 different diameter hex bolts going through it in various directions.

Zero-defects ever since.

[Patrick Varley]

I prefer the inserts that are hex drive. I've had a pretty good experience with the EZ-Lok brand. Definitely agree with Jim on adding a little chamfer to the hole.

https://www.ezlok.com/for-wood/for-soft-wood/ezhex-threaded-inserts-for-soft-wood

Then I just chuck a hex bit into the drill press and turn it by hand, as others have suggested.

[Jamie Buxton]

EZ-Lok makes a very good installation tool. Here's a link to a kit containing it, but you can buy just the installer from many source. https://www.amazon.com/Z-LOK-Threaded-Inserts-Installation/dp/B015CAPI54/ref=sr_1_4?crid=3SDK2ZMO3CSI9&keywords=ez+lok&qid=1686148095&sprefix=ez+lok%2Caps%2C142&sr=8-4 I use it as the tip on a standard screw driver in a power drill. The long extender gives you a good way of aiming the insert so it goes in straight.

I chamber the pilot hole with a countersink. This reduces split-put at the surface. It also helps the insert go in straight.

[mike calabrese]

They are tricky I don't use a ton of them but have adopted a couple of methods that seem to help me.
Soft woods I drill the pilot hole carefully and a little smaller then the thread root diameter.

You know soft wood will crush the smaller root drill might tend to crush the wood "evenly" by guiding the insert with possibly evener:D (I just invented that word) tension all around.

Hardwood I usually try to match the rood diameter for the pilot hole.
Always use some wax to lube the threads

Always in either wood I grind the lead end a little, if it is a straight profile insert, taper it to assist the start into the hole. Not all inserts are made the same . Features like a slight taper. the quality of the finish on the insert, the thread pitch. Thread pitch is a big consideration we know that items like pocket screws and drywall screws usually are offered in two thread pitches fine and coarse. While you will see some variance in the thread form most are pretty coarse threads. The inserts we see are not so much built this way.
I generally do not glue them but epoxy would act like a thread lube if you like to glue set them.
here are some video tips

https://www.youtube.com/watch?v=wifYMPWB1IE

https://www.youtube.com/watch?v=czBiq7w7ONc

https://www.youtube.com/watch?v=t7PP_0lmX-Y

A smash of inserts you can see some will be fun and some you should run
https://www.google.com/search?q=self+tapping+threaded+inserts+for+wood&tbm=isch&hl=en&chips=q:self+tapping+threaded+inserts+for+wood,onl ine_chips:brass+inserts:YmdGOP1_f4o%3D&client=opera&sa=X&ved=2ahUKEwixvcXwr7H_AhUzL1kFHbmjBkMQ4lYoBHoECAEQN Q&biw=1351&bih=619
calabrese55

[glenn bradley]

A purpose built driver or a bolt with the head cutoff and double-nutted in the drill press assures a straight and true start.

[Tom M King]

I use the ones for metal and tap the holes for them just like it's metal instead of wood. A few drops of medium Cyanoacrylate holds them very securely.

The hardest spot was in old window jambs to use removable stops so the old sash can be easily taken out multiple times in the future. I bought some metal drill guides and glued them in drill press drilled holes in a hardwood strip so all the stops would all be interchangeable.

The ones made for wood were a no go in the really old Pine, and I have never since used anything but the ones with machine threads on the outside.

https://www.ezlok.com/for-metal/ezlok-solid-wall-threaded-inserts/ezlok-solid-wall-threaded-inserts-stainless-steel

I melt the Locktite off of them with a propane torch before using in wood.

[Michael Burnside]

Jamie mentioned the tool you should use by EZ-lock. My recommendation is to ONLY use stainless steel versions from EZ-lock. They are super sharp and go into soft or hard wood. They are more expensive, but they plain flat work. I hand drive them in, too numerous to count, they always work great. The other brass inserts with thick threads are garbage IMHO.

[Lee Schierer]

I never use threaded inserts; used them once in poplar. They worked fine for what I needed, but were definitely not driven in squarely to the wood.

So questions...would you guess that was because it was poplar and poplar is super soft? Bad luck? Or is there a method to drive them in properly / squarely? I've seen some folks install the fastener, then chuck it up in the drill press and turn it by hand. This seems like its way overkill, but is that the best way to drive them squarely?

Yes, I do realize how precious I sound asking such a dumb question lol

I use my drill press whenever possible when I install threaded inserts. I hate crooked inserts and ruined pieces of wood.

[Randy Viellenave]

If you can use the inserts without the lip on top, this method should work.
502498

Get a piece of scrap wood, drill straight through with the drill press, then use the drill press to start the insert. Run it all the way through.
502499

When time to use an insert, run it through until it is just poking out
502500

The bottom will slip into the hole, just press down and run it into the material. I have run several hundred using this jig, all of them turned out perfect.

[Patty Hann]

Maybe someone already posted it, but there was a thread on this not too long ago....

https://sawmillcreek.org/showthread.php?287368-Driving-threaded-inserts

I recently inserted 1/4"-20 brass ones in cherry using the drill press method Lee describes... they went in perfectly straight

[Edwin Santos]

Whatever method you use, I learned a good tip somewhere to chamfer the hole with a large countersink bit before driving your insert.

[Patty Hann]

Whatever method you use, I learned a good tip somewhere to chamfer the hole with a large countersink bit before driving your insert.
Ditto on the chamfering...I did that also

[Bill Dufour]

A hand tapper or just use a guide block. For wwing a hand tapping rig is overkill. To make a guide block just bore a guide hole on the drill press to to major diameter of the insert. hardwood should last at least a few projects.
Bill D.
https://www.kbctools.com/catsearch/115/hand-tappers-and-tap-guides

[Bradley Gray]

Hard woods like maple or cherry take machine screw threads really well with no insert.

[Gordon Stump]

502513

I do hundreds of brass knife type threaded insert a year. The jig in the images worked great with a cordless drill. Now I set up a reversible tapping head on a drill press. Due to triple price increases in brass inserts I use zinc inserts on several products. Yes, they will work on hardwood if you drill a larger hole. I eyeball 90 degrees with a cordless drill and let the flare top straighten it out if they go in crooked. Also, backing it out and drilling again straightens it out. I put a dab of epoxy in the threads.


https://youtu.be/Ov86ZW9tvfI

[Jason White]

https://www.woodsmith.com/article/threaded-insert-jig/